Approaches to Studying the Approaches to Studying the Relationships Among Poverty, Air Relationships Among Poverty, Air

Pollution, and Health in Ho Chi Minh Pollution, and Health in Ho Chi Minh City, VietnamCity, Vietnam

Sumi Mehta and Aaron CohenSumi Mehta and Aaron CohenPPublic Health and ublic Health and AAir ir PPollution in ollution in AAsia sia

(The PAPA Program) (The PAPA Program)

OverviewOverview

• Background: air pollution, poverty, and health

• Objective: designing portable study approaches for HCMC context

• Insight from a recent technical visit to HCMC

• Possible Approaches

Why the poor may suffer more Why the poor may suffer more health effects from air pollutionhealth effects from air pollution

• The poor suffer higher exposures to air pollution

• Living close to traffic• Roadside occupational exposures • Small and medium scale enterprises / Cottage

industries• Use of solid fuels for cooking

• The poor are more susceptible to air pollution

• Poor nutrition / immunosuppression• Higher incidence of ‘diseases of poverty’• Lack of timely access to health care

• Limited evidence from the West, but a clear need to explore this issue in the Asian context

Higher Risks Among the Less Higher Risks Among the Less EducatedEducated

• Evidence from HEI Reanalysis

• Attained education inversely associated with PM relative risk in ACS and Six-Cities studies

• An indicator of social class

• Due to differences in true exposure?

• Sensitivity to air pollution?

Studying Air Pollution, Poverty, Studying Air Pollution, Poverty, and Health in HCMCand Health in HCMC

• Initiated at the request of ADB• Identify feasible approaches to

studying poverty, air pollution, and health in HCMC

• Methods appropriate for HCMC• Methods suitable for use in other

cities building an evidence base across

Asian cities

Studying Air Pollution, Poverty, Studying Air Pollution, Poverty, and Health in HCMC: and Health in HCMC:

A Technical Visit to HCMCA Technical Visit to HCMC• An interdisciplinary team of researchers

and local authorities in air quality, exposure assessment, health (epidemiology), social science

• Goals: • identify possible geographic areas/populations

for investigation • who are the poor?• where do they live?

• Evaluate availability, quality, and collection frequency of routinely collected data on air quality, health outcomes

• Assess feasibility of collecting supplemental data

Kirk Smith, Sumi Mehta, Aaron Cohen, Le Van Khoa, Vo Tan Dam, Bjarne Sivertsen, Mr. The, Phan Quynh Nhu, Ms. Van

Collaborators

•ADB

•PAPA

•NILU

•East-West Center

•UC Berkeley

•HEPA

•US AEP

Housing and Poverty in Housing and Poverty in HCMCHCMC

• A housing survey has identified over 100 ‘slum’ areas in HCMC, defined as having 50 or more houses with ‘shanty’ housing structures (DONRE and others)

• ‘Shanty’ housing is highly correlated with income in HCMC

• Concentrated areas of poverty does exist within HCMC

• While the poor used to live mainly along the canals, these are the first areas targeted in resettlement programs

• While many canal-side shanty areas have been cleared, many others still exist

Shanty Areas in Shanty Areas in HCMCHCMC

Canal-Side SlumCanal-Side Slum

Slum and Replacement Slum and Replacement HousingHousing

Health Data in HCMCHealth Data in HCMC

• Quality and availability of data varies tremendously by level of care and speciality• Local clinics report case summaries,

but seldom keep detailed patient records

• Hospitals use similar intake forms, but record keeping systems vary

• Electronic data available at Pediatric Hospital #1, Respiratory Hospital for many years

• Includes financial records (payment exemptions for the poor)

Air Quality Data: Currently Available: 9 Functioning Air Quality Data: Currently Available: 9 Functioning automatic monitoring stations with high quality air quality automatic monitoring stations with high quality air quality

information collected daily (HEPA)information collected daily (HEPA)

Station – Site NOx SO2 O3 CO PM10 Met Classification

DOSTE – District 3 √ √ √ √ √

Urban/Traffic

Tan Son Hoa- Phu Nhuan district

√ √ √ √ Residential

Urban management division – Thu Duc district

√ √ Urban/Industrial

Hong Bang school – District 5

√ √ √ Urban/Traffic

Zoo - District 01

√ √ √ Urban background

Quang Trung software city - District 12

√ √ √ √ Urban background

People’s Committee office - District 02

√ √ √ √ Residential

Thong Nhat hospital – Tan Binh district

√ √ √ √ Urban/Traffic

Education office – Binh Chanh district

√ √ √ Urban/Traffic

Roadside Monitoring Station Roadside Monitoring Station Maintained by HEPA, with Maintained by HEPA, with

assistance from NILUassistance from NILU

Approaches to Exposure Approaches to Exposure AssessmentAssessment

• Modeling approach based on existing air quality data• In progress: spatially resolved air quality

estimates at the ward (zip code) level• Integrate data from air pollution monitors,

traffic density, emission inventories (AirQUIS)• Work conducted by HEPA, with guidance from

NILU

• Key issues relevant to health studies:• Does the model indicate a distribution of

exposures across the city?• How well does the model represent individual /

household exposures?

Approaches to Exposure Approaches to Exposure AssessmentAssessment

• Neighborhood / personal exposure assessment• Validates the modeled estimates of

exposure• Addresses other local ‘hot-spots’/

microenvironments for exposures not included in the exposure model

• Time spent in traffic• Cooking with solid fuels (wood, coal) and/or

poorly combusted kerosene• Environmental tobacco smoke (ETS)• Occupational exposures (street vendors,

traffic police, drivers)

Solid Fuel Use in Canal-Solid Fuel Use in Canal-side Householdside Household

Possible Applications of Exposure Possible Applications of Exposure Estimates in Health Studies Estimates in Health Studies

• Hospital based studies• Case-control, case crossover studies• Use modeled ward level estimates to

represent individual exposures• Use individual / neighborhood

exposures to refine exposure estimates, aid in process of selecting controls

• Community based studies• Prevalence studies conducted during

neighborhood exposure assessment

DiscussionDiscussion

• Health effects of air pollution in Asia are likely to be more severe among the poor, but the evidence base is lacking.

• Informative studies require an integration of data and expertise from aerometrics, exposure assessment, epidemiology, and social science.

• Initial assessment is that such studies can be conducted in HCMC.

• Approaches are being developed with the specific intent to be used in other cities.

Kirk Smith, Sumi Mehta, Aaron Cohen, Le Van Khoa, Vo Tan Dam, Bjarne Sivertsen, Mr. The, Phan Quynh Nhu, Ms. Van

Collaborators

•ADB

•PAPA

•NILU

•East-West Center

•UC Berkeley

•HEPA

•US AEP